Structural properties of Fe49Ni49Ti2 alloy deformed by high pressure torsion

Tetrataenite (L10-FeNi) is a promising candidate for use as a permanent magnet free of rare-earth elements because of its favorable properties such as high magnetic anisotropy and coercivity. We report on structural properties of Fe49Ni49Ti2 alloy after severe plastic deformation (SPD) by high pressure torsion (HPT) technique. The main magnetic and structural characteristics of bulk and HPT materials were determined. As a result of plastic deformation, all samples were obtained with high concentration of defects and stressed state. Low-temperature annealing was used to accelerate the kinetics of phase formation and the possible appearance of nuclei of a stable chemically ordered L10 phase of tetrataenite. Our research shows that it is premature to talk about the formation of even a small amount of phase L10. Additional research needs to be done.